L me s.— Carefully examine the lines of your graphs: some 

 lines may be so faint that they will disappear with reduction, 

 some may be so heavy that they dominate the graph. Reject 

 drawings in which the lines are wavy, jagged, or broken. 



The weight of the lines has much to do with the pleasing 

 appearance of your illustrations. Never enclose the graph 

 in a heavy box or border, as it distracts the eye fronn the 

 main part of the graph. The border or the ordinate and 

 abscissa axes should be only a little heavier than the 

 grid lines, when they are used. The slopes of the graph 

 should be of a line weight sufficiently heavy enough to be 

 the dominant feature in the illustration. 



Lines within the graph should be distinctive, so that 

 they are easily distinguished when the figure is reduced. 

 In lines composed of both long and short dashes, naake the 

 long dashes at least three times the length of the short 

 dashes. Be sure that there is adequate space left between 

 dashes, since the spaces also become smaller with reduction. 

 (You can check the adequacy of the spaces with a reducing 

 glass.) Also, remember that broken lines appear heavier 

 than solid lines, so a fine pen should be used to make the 

 dashed or broken lines. 



In complex graphs avoid intersecting lines that are hard 

 to read or that fill with ink during printing. Sometimes grid 

 lines are used when tick marks would be sufficient and in 

 many instances omission of grid lines would produce a 

 sharper, more legible drawing. When grid lines are neces- 

 sary do not permit them to pass through symbols, lettering, 

 or lines of the graph. If it is necessary to set off a key or 

 explanations of the symbols from the main part of the graph, 

 enclose them neatly in a box. 



Outline bar graphs and histograms with a pen to ensure 

 sharp, square corners. Different patterns of zipitone can 

 then be used or the bars crosshatched, stippled, or filled 

 solidly with ink. Caution: Avoid large areas of black, as 

 such illustrations present an unpleasant contrast with 

 other figures and with the printed page. Also, do not stipple 

 so heavily and closely that the dots nnerge when the illustra- 

 tion is reduced. Select zipitone patterns that will be distinct 

 after considerable reduction. 



Curves should be well-drawn; freehand drawing is diffi- 

 cult and may give a careless appearance to the figure. 



Lettering.-- San- serii lettering, such as that produced by 

 a number of lettering sets available on the market, is 

 preferred. It is moi-e legible after reduction than is serif 

 lettering, in which the letters are thin- stemmed and footed, 

 as generally used in text. Well-formed letters are uniform 



12 



